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-rw-r--r--drivers/pwm/core.c42
-rw-r--r--drivers/pwm/pwm-atmel-hlcdc.c4
-rw-r--r--drivers/pwm/pwm-atmel.c63
-rw-r--r--drivers/pwm/pwm-bcm-kona.c9
-rw-r--r--drivers/pwm/pwm-img.c76
-rw-r--r--drivers/pwm/pwm-lpss-pci.c2
-rw-r--r--drivers/pwm/pwm-mxs.c8
-rw-r--r--drivers/pwm/pwm-pca9685.c2
-rw-r--r--drivers/pwm/pwm-samsung.c33
9 files changed, 196 insertions, 43 deletions
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 810aef3f4c3e..3a7769fe53de 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -223,13 +223,16 @@ void *pwm_get_chip_data(struct pwm_device *pwm)
EXPORT_SYMBOL_GPL(pwm_get_chip_data);
/**
- * pwmchip_add() - register a new PWM chip
+ * pwmchip_add_with_polarity() - register a new PWM chip
* @chip: the PWM chip to add
+ * @polarity: initial polarity of PWM channels
*
* Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
- * will be used.
+ * will be used. The initial polarity for all channels is specified by the
+ * @polarity parameter.
*/
-int pwmchip_add(struct pwm_chip *chip)
+int pwmchip_add_with_polarity(struct pwm_chip *chip,
+ enum pwm_polarity polarity)
{
struct pwm_device *pwm;
unsigned int i;
@@ -259,6 +262,7 @@ int pwmchip_add(struct pwm_chip *chip)
pwm->chip = chip;
pwm->pwm = chip->base + i;
pwm->hwpwm = i;
+ pwm->polarity = polarity;
radix_tree_insert(&pwm_tree, pwm->pwm, pwm);
}
@@ -279,6 +283,19 @@ out:
mutex_unlock(&pwm_lock);
return ret;
}
+EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity);
+
+/**
+ * pwmchip_add() - register a new PWM chip
+ * @chip: the PWM chip to add
+ *
+ * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base
+ * will be used. The initial polarity for all channels is normal.
+ */
+int pwmchip_add(struct pwm_chip *chip)
+{
+ return pwmchip_add_with_polarity(chip, PWM_POLARITY_NORMAL);
+}
EXPORT_SYMBOL_GPL(pwmchip_add);
/**
@@ -573,7 +590,7 @@ EXPORT_SYMBOL_GPL(of_pwm_get);
* @table: array of consumers to register
* @num: number of consumers in table
*/
-void __init pwm_add_table(struct pwm_lookup *table, size_t num)
+void pwm_add_table(struct pwm_lookup *table, size_t num)
{
mutex_lock(&pwm_lookup_lock);
@@ -586,6 +603,23 @@ void __init pwm_add_table(struct pwm_lookup *table, size_t num)
}
/**
+ * pwm_remove_table() - unregister PWM device consumers
+ * @table: array of consumers to unregister
+ * @num: number of consumers in table
+ */
+void pwm_remove_table(struct pwm_lookup *table, size_t num)
+{
+ mutex_lock(&pwm_lookup_lock);
+
+ while (num--) {
+ list_del(&table->list);
+ table++;
+ }
+
+ mutex_unlock(&pwm_lookup_lock);
+}
+
+/**
* pwm_get() - look up and request a PWM device
* @dev: device for PWM consumer
* @con_id: consumer name
diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
index 522f7075bb1a..fa5feaba25a5 100644
--- a/drivers/pwm/pwm-atmel-hlcdc.c
+++ b/drivers/pwm/pwm-atmel-hlcdc.c
@@ -225,6 +225,10 @@ static const struct of_device_id atmel_hlcdc_dt_ids[] = {
.compatible = "atmel,sama5d3-hlcdc",
.data = &atmel_hlcdc_pwm_sama5d3_errata,
},
+ {
+ .compatible = "atmel,sama5d4-hlcdc",
+ .data = &atmel_hlcdc_pwm_sama5d3_errata,
+ },
{ /* sentinel */ },
};
diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index d3c22de9ee47..a947c9095d9d 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -8,9 +8,11 @@
*/
#include <linux/clk.h>
+#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
@@ -21,6 +23,7 @@
#define PWM_ENA 0x04
#define PWM_DIS 0x08
#define PWM_SR 0x0C
+#define PWM_ISR 0x1C
/* Bit field in SR */
#define PWM_SR_ALL_CH_ON 0x0F
@@ -60,6 +63,9 @@ struct atmel_pwm_chip {
struct clk *clk;
void __iomem *base;
+ unsigned int updated_pwms;
+ struct mutex isr_lock; /* ISR is cleared when read, ensure only one thread does that */
+
void (*config)(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long dty, unsigned long prd);
};
@@ -144,6 +150,10 @@ static int atmel_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
val = (val & ~PWM_CMR_CPRE_MSK) | (pres & PWM_CMR_CPRE_MSK);
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWM_CMR, val);
atmel_pwm->config(chip, pwm, dty, prd);
+ mutex_lock(&atmel_pwm->isr_lock);
+ atmel_pwm->updated_pwms |= atmel_pwm_readl(atmel_pwm, PWM_ISR);
+ atmel_pwm->updated_pwms &= ~(1 << pwm->hwpwm);
+ mutex_unlock(&atmel_pwm->isr_lock);
clk_disable(atmel_pwm->clk);
return ret;
@@ -155,24 +165,25 @@ static void atmel_pwm_config_v1(struct pwm_chip *chip, struct pwm_device *pwm,
struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
unsigned int val;
- if (test_bit(PWMF_ENABLED, &pwm->flags)) {
- /*
- * If the PWM channel is enabled, using the update register,
- * it needs to set bit 10 of CMR to 0
- */
- atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CUPD, dty);
- val = atmel_pwm_ch_readl(atmel_pwm, pwm->hwpwm, PWM_CMR);
- val &= ~PWM_CMR_UPD_CDTY;
- atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWM_CMR, val);
- } else {
- /*
- * If the PWM channel is disabled, write value to duty and
- * period registers directly.
- */
- atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CDTY, dty);
- atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CPRD, prd);
- }
+ atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CUPD, dty);
+
+ val = atmel_pwm_ch_readl(atmel_pwm, pwm->hwpwm, PWM_CMR);
+ val &= ~PWM_CMR_UPD_CDTY;
+ atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWM_CMR, val);
+
+ /*
+ * If the PWM channel is enabled, only update CDTY by using the update
+ * register, it needs to set bit 10 of CMR to 0
+ */
+ if (test_bit(PWMF_ENABLED, &pwm->flags))
+ return;
+ /*
+ * If the PWM channel is disabled, write value to duty and period
+ * registers directly.
+ */
+ atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CDTY, dty);
+ atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CPRD, prd);
}
static void atmel_pwm_config_v2(struct pwm_chip *chip, struct pwm_device *pwm,
@@ -242,7 +253,22 @@ static int atmel_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
static void atmel_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
+ unsigned long timeout = jiffies + 2 * HZ;
+
+ /*
+ * Wait for at least a complete period to have passed before disabling a
+ * channel to be sure that CDTY has been updated
+ */
+ mutex_lock(&atmel_pwm->isr_lock);
+ atmel_pwm->updated_pwms |= atmel_pwm_readl(atmel_pwm, PWM_ISR);
+
+ while (!(atmel_pwm->updated_pwms & (1 << pwm->hwpwm)) &&
+ time_before(jiffies, timeout)) {
+ usleep_range(10, 100);
+ atmel_pwm->updated_pwms |= atmel_pwm_readl(atmel_pwm, PWM_ISR);
+ }
+ mutex_unlock(&atmel_pwm->isr_lock);
atmel_pwm_writel(atmel_pwm, PWM_DIS, 1 << pwm->hwpwm);
clk_disable(atmel_pwm->clk);
@@ -357,6 +383,8 @@ static int atmel_pwm_probe(struct platform_device *pdev)
atmel_pwm->chip.npwm = 4;
atmel_pwm->chip.can_sleep = true;
atmel_pwm->config = data->config;
+ atmel_pwm->updated_pwms = 0;
+ mutex_init(&atmel_pwm->isr_lock);
ret = pwmchip_add(&atmel_pwm->chip);
if (ret < 0) {
@@ -378,6 +406,7 @@ static int atmel_pwm_remove(struct platform_device *pdev)
struct atmel_pwm_chip *atmel_pwm = platform_get_drvdata(pdev);
clk_unprepare(atmel_pwm->clk);
+ mutex_destroy(&atmel_pwm->isr_lock);
return pwmchip_remove(&atmel_pwm->chip);
}
diff --git a/drivers/pwm/pwm-bcm-kona.c b/drivers/pwm/pwm-bcm-kona.c
index 02bc048892a9..7af8fea2dc5b 100644
--- a/drivers/pwm/pwm-bcm-kona.c
+++ b/drivers/pwm/pwm-bcm-kona.c
@@ -266,18 +266,15 @@ static int kona_pwmc_probe(struct platform_device *pdev)
return ret;
}
- /* Set smooth mode, push/pull, and normal polarity for all channels */
- for (chan = 0; chan < kp->chip.npwm; chan++) {
- value |= (1 << PWM_CONTROL_SMOOTH_SHIFT(chan));
+ /* Set push/pull for all channels */
+ for (chan = 0; chan < kp->chip.npwm; chan++)
value |= (1 << PWM_CONTROL_TYPE_SHIFT(chan));
- value |= (1 << PWM_CONTROL_POLARITY_SHIFT(chan));
- }
writel(value, kp->base + PWM_CONTROL_OFFSET);
clk_disable_unprepare(kp->clk);
- ret = pwmchip_add(&kp->chip);
+ ret = pwmchip_add_with_polarity(&kp->chip, PWM_POLARITY_INVERSED);
if (ret < 0)
dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
diff --git a/drivers/pwm/pwm-img.c b/drivers/pwm/pwm-img.c
index 476171a768d6..8a029f9bc18c 100644
--- a/drivers/pwm/pwm-img.c
+++ b/drivers/pwm/pwm-img.c
@@ -16,6 +16,7 @@
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/regmap.h>
@@ -38,7 +39,22 @@
#define PERIP_PWM_PDM_CONTROL_CH_MASK 0x1
#define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch) ((ch) * 4)
-#define MAX_TMBASE_STEPS 65536
+/*
+ * PWM period is specified with a timebase register,
+ * in number of step periods. The PWM duty cycle is also
+ * specified in step periods, in the [0, $timebase] range.
+ * In other words, the timebase imposes the duty cycle
+ * resolution. Therefore, let's constraint the timebase to
+ * a minimum value to allow a sane range of duty cycle values.
+ * Imposing a minimum timebase, will impose a maximum PWM frequency.
+ *
+ * The value chosen is completely arbitrary.
+ */
+#define MIN_TMBASE_STEPS 16
+
+struct img_pwm_soc_data {
+ u32 max_timebase;
+};
struct img_pwm_chip {
struct device *dev;
@@ -47,6 +63,9 @@ struct img_pwm_chip {
struct clk *sys_clk;
void __iomem *base;
struct regmap *periph_regs;
+ int max_period_ns;
+ int min_period_ns;
+ const struct img_pwm_soc_data *data;
};
static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip)
@@ -72,24 +91,31 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
u32 val, div, duty, timebase;
unsigned long mul, output_clk_hz, input_clk_hz;
struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip);
+ unsigned int max_timebase = pwm_chip->data->max_timebase;
+
+ if (period_ns < pwm_chip->min_period_ns ||
+ period_ns > pwm_chip->max_period_ns) {
+ dev_err(chip->dev, "configured period not in range\n");
+ return -ERANGE;
+ }
input_clk_hz = clk_get_rate(pwm_chip->pwm_clk);
output_clk_hz = DIV_ROUND_UP(NSEC_PER_SEC, period_ns);
mul = DIV_ROUND_UP(input_clk_hz, output_clk_hz);
- if (mul <= MAX_TMBASE_STEPS) {
+ if (mul <= max_timebase) {
div = PWM_CTRL_CFG_NO_SUB_DIV;
timebase = DIV_ROUND_UP(mul, 1);
- } else if (mul <= MAX_TMBASE_STEPS * 8) {
+ } else if (mul <= max_timebase * 8) {
div = PWM_CTRL_CFG_SUB_DIV0;
timebase = DIV_ROUND_UP(mul, 8);
- } else if (mul <= MAX_TMBASE_STEPS * 64) {
+ } else if (mul <= max_timebase * 64) {
div = PWM_CTRL_CFG_SUB_DIV1;
timebase = DIV_ROUND_UP(mul, 64);
- } else if (mul <= MAX_TMBASE_STEPS * 512) {
+ } else if (mul <= max_timebase * 512) {
div = PWM_CTRL_CFG_SUB_DIV0_DIV1;
timebase = DIV_ROUND_UP(mul, 512);
- } else if (mul > MAX_TMBASE_STEPS * 512) {
+ } else if (mul > max_timebase * 512) {
dev_err(chip->dev,
"failed to configure timebase steps/divider value\n");
return -EINVAL;
@@ -143,11 +169,27 @@ static const struct pwm_ops img_pwm_ops = {
.owner = THIS_MODULE,
};
+static const struct img_pwm_soc_data pistachio_pwm = {
+ .max_timebase = 255,
+};
+
+static const struct of_device_id img_pwm_of_match[] = {
+ {
+ .compatible = "img,pistachio-pwm",
+ .data = &pistachio_pwm,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, img_pwm_of_match);
+
static int img_pwm_probe(struct platform_device *pdev)
{
int ret;
+ u64 val;
+ unsigned long clk_rate;
struct resource *res;
struct img_pwm_chip *pwm;
+ const struct of_device_id *of_dev_id;
pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
if (!pwm)
@@ -160,6 +202,11 @@ static int img_pwm_probe(struct platform_device *pdev)
if (IS_ERR(pwm->base))
return PTR_ERR(pwm->base);
+ of_dev_id = of_match_device(img_pwm_of_match, &pdev->dev);
+ if (!of_dev_id)
+ return -ENODEV;
+ pwm->data = of_dev_id->data;
+
pwm->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
"img,cr-periph");
if (IS_ERR(pwm->periph_regs))
@@ -189,6 +236,17 @@ static int img_pwm_probe(struct platform_device *pdev)
goto disable_sysclk;
}
+ clk_rate = clk_get_rate(pwm->pwm_clk);
+
+ /* The maximum input clock divider is 512 */
+ val = (u64)NSEC_PER_SEC * 512 * pwm->data->max_timebase;
+ do_div(val, clk_rate);
+ pwm->max_period_ns = val;
+
+ val = (u64)NSEC_PER_SEC * MIN_TMBASE_STEPS;
+ do_div(val, clk_rate);
+ pwm->min_period_ns = val;
+
pwm->chip.dev = &pdev->dev;
pwm->chip.ops = &img_pwm_ops;
pwm->chip.base = -1;
@@ -228,12 +286,6 @@ static int img_pwm_remove(struct platform_device *pdev)
return pwmchip_remove(&pwm_chip->chip);
}
-static const struct of_device_id img_pwm_of_match[] = {
- { .compatible = "img,pistachio-pwm", },
- { }
-};
-MODULE_DEVICE_TABLE(of, img_pwm_of_match);
-
static struct platform_driver img_pwm_driver = {
.driver = {
.name = "img-pwm",
diff --git a/drivers/pwm/pwm-lpss-pci.c b/drivers/pwm/pwm-lpss-pci.c
index cf20d2beacdd..45042c1b2046 100644
--- a/drivers/pwm/pwm-lpss-pci.c
+++ b/drivers/pwm/pwm-lpss-pci.c
@@ -44,8 +44,10 @@ static void pwm_lpss_remove_pci(struct pci_dev *pdev)
}
static const struct pci_device_id pwm_lpss_pci_ids[] = {
+ { PCI_VDEVICE(INTEL, 0x0ac8), (unsigned long)&pwm_lpss_bsw_info},
{ PCI_VDEVICE(INTEL, 0x0f08), (unsigned long)&pwm_lpss_byt_info},
{ PCI_VDEVICE(INTEL, 0x0f09), (unsigned long)&pwm_lpss_byt_info},
+ { PCI_VDEVICE(INTEL, 0x1ac8), (unsigned long)&pwm_lpss_bsw_info},
{ PCI_VDEVICE(INTEL, 0x2288), (unsigned long)&pwm_lpss_bsw_info},
{ PCI_VDEVICE(INTEL, 0x2289), (unsigned long)&pwm_lpss_bsw_info},
{ },
diff --git a/drivers/pwm/pwm-mxs.c b/drivers/pwm/pwm-mxs.c
index f75ecb09d97d..b430811e14f5 100644
--- a/drivers/pwm/pwm-mxs.c
+++ b/drivers/pwm/pwm-mxs.c
@@ -35,6 +35,10 @@
#define PERIOD_CDIV(div) (((div) & 0x7) << 20)
#define PERIOD_CDIV_MAX 8
+static const unsigned int cdiv[PERIOD_CDIV_MAX] = {
+ 1, 2, 4, 8, 16, 64, 256, 1024
+};
+
struct mxs_pwm_chip {
struct pwm_chip chip;
struct clk *clk;
@@ -54,13 +58,13 @@ static int mxs_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
rate = clk_get_rate(mxs->clk);
while (1) {
- c = rate / (1 << div);
+ c = rate / cdiv[div];
c = c * period_ns;
do_div(c, 1000000000);
if (c < PERIOD_PERIOD_MAX)
break;
div++;
- if (div > PERIOD_CDIV_MAX)
+ if (div >= PERIOD_CDIV_MAX)
return -EINVAL;
}
diff --git a/drivers/pwm/pwm-pca9685.c b/drivers/pwm/pwm-pca9685.c
index 3fb775ded0df..34b5c275a92a 100644
--- a/drivers/pwm/pwm-pca9685.c
+++ b/drivers/pwm/pwm-pca9685.c
@@ -202,7 +202,7 @@ static const struct pwm_ops pca9685_pwm_ops = {
.owner = THIS_MODULE,
};
-static struct regmap_config pca9685_regmap_i2c_config = {
+static const struct regmap_config pca9685_regmap_i2c_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = PCA9685_NUMREGS,
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
index 3e9b5835a4af..ada2d326dc3e 100644
--- a/drivers/pwm/pwm-samsung.c
+++ b/drivers/pwm/pwm-samsung.c
@@ -269,12 +269,31 @@ static void pwm_samsung_disable(struct pwm_chip *chip, struct pwm_device *pwm)
spin_unlock_irqrestore(&samsung_pwm_lock, flags);
}
+static void pwm_samsung_manual_update(struct samsung_pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ unsigned int tcon_chan = to_tcon_channel(pwm->hwpwm);
+ u32 tcon;
+ unsigned long flags;
+
+ spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+ tcon = readl(chip->base + REG_TCON);
+ tcon |= TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, chip->base + REG_TCON);
+
+ tcon &= ~TCON_MANUALUPDATE(tcon_chan);
+ writel(tcon, chip->base + REG_TCON);
+
+ spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct samsung_pwm_chip *our_chip = to_samsung_pwm_chip(chip);
struct samsung_pwm_channel *chan = pwm_get_chip_data(pwm);
- u32 tin_ns = chan->tin_ns, tcnt, tcmp;
+ u32 tin_ns = chan->tin_ns, tcnt, tcmp, oldtcmp;
/*
* We currently avoid using 64bit arithmetic by using the
@@ -288,6 +307,7 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
return 0;
tcnt = readl(our_chip->base + REG_TCNTB(pwm->hwpwm));
+ oldtcmp = readl(our_chip->base + REG_TCMPB(pwm->hwpwm));
/* We need tick count for calculation, not last tick. */
++tcnt;
@@ -335,6 +355,16 @@ static int pwm_samsung_config(struct pwm_chip *chip, struct pwm_device *pwm,
writel(tcnt, our_chip->base + REG_TCNTB(pwm->hwpwm));
writel(tcmp, our_chip->base + REG_TCMPB(pwm->hwpwm));
+ /*
+ * In case the PWM is currently at 100% duty cycle, force a manual
+ * update to prevent the signal staying high if the PWM is disabled
+ * shortly afer this update (before it autoreloaded the new values).
+ */
+ if (oldtcmp == (u32) -1) {
+ dev_dbg(our_chip->chip.dev, "Forcing manual update");
+ pwm_samsung_manual_update(our_chip, pwm);
+ }
+
chan->period_ns = period_ns;
chan->tin_ns = tin_ns;
chan->duty_ns = duty_ns;
@@ -426,6 +456,7 @@ static const struct of_device_id samsung_pwm_matches[] = {
{ .compatible = "samsung,exynos4210-pwm", .data = &s5p64x0_variant },
{},
};
+MODULE_DEVICE_TABLE(of, samsung_pwm_matches);
static int pwm_samsung_parse_dt(struct samsung_pwm_chip *chip)
{
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-25 22:12:39 +0300